In contrast with Westminster system cabinets, which generally need only be backed by a majority of legislators, ministerial positions in the Northern Ireland Executive are allocated to parties with significant representation in the Assembly. With the exception of justice, the number of ministries to which each party is entitled is determined by the D'Hondt system.

The Executive cannot function if either of the two largest parties refuse to take part, as these parties are allocated the First Minister and deputy First Minister positions. However, other parties are not required to enter the Executive even if they are entitled to do so; instead, they can choose to go into opposition if they wish. There were some calls for the SDLP and the UUP to enter opposition after the 2007 Assembly elections,[4] but ultimately the two parties chose to take the seats in the Executive to which they were entitled.

In 2010, an exception to the D'Hondt system for allocating the number of ministerial portfolios was made under the Hillsborough Castle Agreement to allow the cross-community Alliance Party of Northern Ireland to hold the politically-contentious policing and justice brief when most of those powers were devolved to the Assembly. Devolution took place on 12 April 2010.

Under D'Hondt, the SDLP would have been entitled to the extra ministerial seat on the revised Executive created by the devolution of policing and justice. Accordingly both the UUP and SDLP protested that Alliance was not entitled, under the rules of the Good Friday Agreement, to fill the portfolio and refused to support this move. However, Alliance leader David Ford was elected Minister with the support of the Democratic Unionist Party and Sinn Féin.

The Ministerial Code allows any 3 ministers to request a cross-community vote. The quorum for voting is 7 ministers. At present, the Executive consists of 6 unionist, 5 nationalist and 2 other (Alliance Party) ministers.

The current system of devolution has succeeded long periods of direct rule (1974–1999 and 2002–2007), when the Northern Ireland Civil Service had a considerable influence on government policy. The legislation which established new departments in 1999 affirmed that "the functions of a department shall at all times be exercised subject to the direction and control of the Minister".[7] Ministerial powers can be conferred by an Act of the Assembly[8] and ministers can also exercise executive powers which are vested in the Crown.[9]

Ministerial decisions can be challenged by a petition of 30 Northern Ireland Assembly members. This action can be taken for alleged breaches of the Ministerial Code and on matters of public importance. The Speaker of the Assembly must consult political party leaders in the Assembly (who are often also ministers) before deciding whether the subject is a matter of public importance. Successful petitions will then be considered by the Executive.[13]

The number of ministers and their responsibilities can be changed when a department is being established or dissolved. The proposal must be made by the First Minister and the deputy First Minister and be carried by a cross-community vote in the Assembly. The number of departments was initially limited to 10 but this increased to 11 upon the devolution of justice.[14]

Ministers are disqualified from holding office if appointed to the Government of Ireland or as the chairman or deputy chairman of an Oireachtas (Irish Parliament) committee.[15]

enhancing and developing Ulster Scots language, heritage and culture; and

tackling poverty, social exclusion and patterns of deprivation based on objective need.[16][17]

The Office of the First Minister and Deputy First Minister published a child poverty strategy in March 2011.[18] The wider anti-poverty strategy was carried over from direct rule in November 2006.[19] As of November 2011, neither an Irish language strategy nor an Ulster Scots strategy had been adopted. The Department of Culture, Arts and Leisure states that a Strategy for Indigenous or Regional Minority Languages "will be presented to the Executive in due course".[20]

However, the Executive did not meet between 19 June 2008 and 20 November 2008 due to a boycott by Sinn Féin. This took place during a dispute between the DUP and Sinn Féin over the devolution of policing and justice powers.[33] Policing and justice powers were devolved on 12 April 2010, with the Alliance Party of Northern Ireland holding the position of Minister of Justice in the Executive from that date.[34]

1. Rejected referendums are italicised. The others were fully or partially approved.
2. There is no law-making body for any regionally devolved area.
3. Administrations of regionally devolved araes are omitted.Category